1. Field of the Invention
This invention pertains to an attachment for fork lifts. More particularly, this invention pertains to a fork lift attachment which enables the lifting and handling of cylindrical drums.
2. Description of the Prior Art
In the prior art, many attachments have been proposed to enable a fork lift truck to handle cylindrical drums. See, for example, U.S. Pat. Nos. 3,971,485; 3,512,670; 2,842,275; and 3,410,431.
As shown in U.S. Pat. No. 3,971,485, the prior art includes clamps rotatably carried on the distal ends of pivoting arms. The pivoting arms are pivotally attached to a frame which may be releasably connected to the forks of a fork lift truck. In the aforementioned U.S. Pat. No. 3,971,485, fluid pressure actuators are used to rotate the clamps and pivot the arms.
In constructing a fork lift attachment for handling drums, it is necessary to provide a design which is of low cost manufacture and reliable performance. Also, such a design should preferably include means for retaining a drum in a grasped state in the event of loss of fluid power to the fluid power actuators. It is one of the objects of the present invention to meet this need.